In recent years, there is an increasing tendency to use a glass having an infrared ray shielding performance (hereinafter, referred to as an infrared ray shielding glass) for a window glass for a vehicle for the purpose of suppressing the increase in temperature inside a vehicle and reducing the cooling load. Conventionally, as an infrared ray shielding glass, a film-laminated glass sheet is used on the surface of which a conductive thin film of various types of metal or metal oxides is laminated, and solar radiation energy entering the inside a vehicle is largely cut off by the function of these films.
However, it is known that the infrared ray shielding glass not only cuts off infrared rays but also interrupts electromagnetic waves of a mobile phone. In addition, in the United States, it is mandatory to equip a vehicle with a TPMS (Tire Pressure Monitoring System) which detects air pressure of tires to warn deficiency air pressure of the tires. In this TPMS, for example, infrared signals are sent from transmitters integrated with tire valves to a receiver on a vehicle body.
Further, in recent years, as systems employing infrared rays, keyless entry system and garage door openers are also prevailing. The keyless entry system and the garage door openers are a system in which an infrared signal is sent from a transmitter inside a vehicle to a receiver on a garage, thereby opening and closing the door or the garage.
Thus, in order to cause these systems to operate properly, the glass needs to have an electromagnetic wave transmitting performance.
In a window glass for a vehicle described in Patent Document 1, a transmitter/receiver is attached directly to part of a window glass on an inner side of a vehicle, and an infrared ray shielding layer is not provided only in the position where the transmitter/receiver is attached, whereby an electromagnetic wave communication is permitted between an exterior of the vehicle and the transmitter/receiver while cutting off solar radiation energy.